Considerable development effort is currently being expended on the development of hydrogen and oxygen consuming fuel cells, and there is also interest in hydrogen burning engines. Such power systems require means for storage of hydrogen fuel which hold hydrogen in a safe form at ambient conditions and which are capable of quickly receiving and releasing hydrogen. In the case of automotive vehicles, fuel storage is required to be on-board the vehicle, and storage of hydrogen gas at high pressure is generally not acceptable for such applications.
These requirements have led to the study and development of solid-state compounds for temporary storage of hydrogen, often as hydrides. For example, sodium alanate, NaAlH4, can be heated to release hydrogen gas, and a mixture of lithium amide, LiNH2, and lithium hydride, LiH, can be heated and reacted with the same effect. Despite such progress, however, no known solid-state system currently satisfies targets for on-board vehicular hydrogen storage.
Certain compounds, XLi2Mg, where X is Al, Zn, Ga, Ge, Ag, Cd, In, Sn, Sb, Au, Hg, Tl, Pb, and Bi are known to exist. It is an object of this invention to determine whether corresponding hydrides, XLi2MgHn, may be formed that could serve with such compounds in hydrogen storage combinations of hydrogen releasing and hydrogen accepting compounds.